1. Field of the Invention
The present invention relates to a substrate etching apparatus, and more particularly, to a substrate etching apparatus for preventing the surface of a flat panel display panel from being damaged and improving thickness uniformity.
2. Description of the Related Art
Consumer's interest in reduction in the thickness of a flat panel display panel is increasing. Etching methods are used to reduce the thickness of the flat panel display panel.
The etching methods include a dipping etching method in which a flat panel display panel is dipped in an etching solution to etch the flat panel display panel, and a shower etching method in which an etching solution is sprayed to both faces of a flat panel display panel that is vertically standing to etch the flat panel display panel.
The dipping etching method has drawbacks in that thickness uniformity is low over the entire area of a flat panel display panel, etch rate deterioration speed is high, a large etching solution bath is required so that the etching solution bath is difficult to manage, and it is difficult to remove sludge generated during an etching process.
The shower etching method has limitations in reducing the thickness of a flat panel display panel because the flat panel display panel is warped when the spray pressure of an etching solution sprayed to both faces of the flat panel display panel is unbalanced.
The shower etching method has a problem in that etching solution spray nozzles can be easily clogged by sludge to stain the surface of the flat panel display panel.
Furthermore, the shower etching method requires a wide space for parallel etching because it uses nozzles that spray an etching solution to both faces of the flat panel display panel. The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.